BKDR_YUSI.A

 Analysis by: Rika Joi Gregorio

 PLATFORM:

Windows 2000, Windows Server 2003, Windows XP (32-bit, 64-bit), Windows Vista (32-bit, 64-bit), Windows 7 (32-bit, 64-bit)

 OVERALL RISK RATING:
 DAMAGE POTENTIAL:
 DISTRIBUTION POTENTIAL:
 REPORTED INFECTION:
 INFORMATION EXPOSURE:

  • Threat Type: Backdoor

  • Destructiveness: No

  • Encrypted: Yes

  • In the wild: Yes

  OVERVIEW

Infection Channel:

Downloaded from the Internet, Dropped by other malware


This backdoor may be dropped by other malware. It arrives as a component bundled with malware/grayware packages.

It does not have any propagation routine.

It executes commands from a remote malicious user, effectively compromising the affected system. It connects to a website to send and receive information.

It does not drop any other file.

It requires its main component to successfully perform its intended routine.

  TECHNICAL DETAILS

File Size:

28,672 bytes

File Type:

DLL

Initial Samples Received Date:

22 Aug 2013

Payload:

Connects to URLs/IPs, Collects system information, Downloads files

Arrival Details

This backdoor may be dropped by other malware.

It arrives as a component bundled with malware/grayware packages.

Propagation

This backdoor does not have any propagation routine.

Backdoor Routine

This backdoor executes the following commands from a remote malicious user:

  • View file list
  • Upload files
  • Download files
  • Execute arbitrary code/files
  • Delete files
  • View file information
  • Start remote shell execution
  • Stop remote shell execution
  • View task list

It connects to the following websites to send and receive information:

  • www.{BLOCKED}ebnews.com/test/order.asp
  • www.{BLOCKED}ebnews.com/test/space.asp

Dropping Routine

This backdoor does not drop any other file.

Download Routine

This backdoor connects to the following website(s) to download and execute a malicious file:

  • www.{BLOCKED}ebnews.com/test/download.asp

Information Theft

This backdoor gathers the following data:

  • Malware Version
  • OS Version
  • Disk Information
  • Logon Time
  • Local Time
  • Public and Private IP Addresses
  • Language ID
  • Product Name
  • Product ID

Other Details

This backdoor connects to the following URL(s) to check for an Internet connection:

  • www.{BLOCKED}ebnews.com/test/alive.asp

It connects to the following URL(s) to get the affected system's IP address:

  • www.{BLOCKED}ebnews.com/test/getip.asp

It requires its main component to successfully perform its intended routine.

It uploads files to the following website(s):

  • www.{BLOCKED}ebnews.com/test/upload.asp

NOTES:

It does not have rootkit capabilities.

It does not exploit any vulnerability.

  SOLUTION

Minimum Scan Engine:

9.300

FIRST VSAPI PATTERN FILE:

10.234.05

FIRST VSAPI PATTERN DATE:

23 Aug 2013

VSAPI OPR PATTERN File:

10.235.00

VSAPI OPR PATTERN Date:

24 Aug 2013

Step 1

Before doing any scans, Windows XP, Windows Vista, and Windows 7 users must disable System Restore to allow full scanning of their computers.

Step 2

Scan your computer with your Trend Micro product to delete files detected as BKDR_YUSI.A. If the detected files have already been cleaned, deleted, or quarantined by your Trend Micro product, no further step is required. You may opt to simply delete the quarantined files. Please check this Knowledge Base page for more information.


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